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Biomedical subjects

Z Gu

Publications and source records attributed to Z Gu.

At least 145 records · Page 8Linked to original sources

[Cloning and sequencing of VH and VL genes of an anti-human lung adenocarcinoma monoclonal antibody].

By comparing the conserved regions at each end of the nucleotide sequences of murine germ-line genes encoding FR1 and FR4 regions of immunoglobulin heavy and light chain variable regions, we designed two sets of primer for amplification of VH and VL genes. Hybridoma cell WLA-2C4, secreting an antihuman lung adenocarcinoma McAb, was cultured and the genome DNA was extracted and used as template for PCR. After PCR the desired VH and VL fragments were amplified. The PCR products were then cloned into pUC19 vector. By screening and identification, several recombinants that had been inserted with the target fragments were obtained. Then they were sequenced with Sanger's method. It was confirmed by computer-assisted comparative sequence analysis that clones of full-length and potentially functional VH and VL genes from the hybridoma cell line WLA-2C4 were ob-tained.

Adenocarcinoma↗

[Amplification, cloning and sequence analysis of the variable region genes of monoclonal antibody against human bladder carcinoma].

We have designed two sets of oligonucleotide primers to amplify the immunoglobulin heavy- and light-chain variable region genes from genomic DNA by the polymerase chain reaction, PCR. The genomic DNA was extracted from hybridoma BDI-1 cell, which secrets a monoclonal antibody against human bladder carcinoma. The primers contain special restriction sites that allow the variable region genes to be easy to cloning for sequencing and expression. The PCR products were ligated to plasmid PUC19. The recombinants were sequenced with Sanger's method. It was proved that a full-length VH and V kappa genes was 366 and 324 base pairs respectively. Comparaing with other published sequences, the VH gene was a member of mouse heavy-chain VH subgroup II and originated from rearrangement of VH, Dsp2.2 and JH4; the V kappa gene was V kappa subgroup IV and from V kappa and J kappa 4. It was suggested that obtained VH and V kappa genes were potentially functional genes of the monoclonal antibody against human bladder carcinoma.

Antibodies, Monoclonal↗

[A study of intraarticular irrigation-injection therapy of temporomandibular joint and its mechanism].

According to the research that there were some immune and inflammatory substances in the synovial fluid of temporomandibular joint disturbance syndrome (TMJDS), we improved the traditional intraarticular injection and developed an intraarticular irrigation-injection therapy to treat 43 cases of TMJDS and got a good result. The controls include two groups, the simple rinsing and the traditional injection. Statistical analysis showed a highly significant difference in the effects between test and control groups. In order to study the mechanism of the therapy, the tumor necrosis factor (TNF) in synovial fluid of 8 cases were assessed. It was found that the concentration of TNF was reduced markedly after treatment. We think that the new therapy is effectable for TMJDS and could be used widely.

Adult↗

[A primary study on treatment of intracranial hematomas with specially designed needle puncture].

We treat hematomas by special designed needles and other techniques for breaking and liquefying hematoma. This method is easy to learn and needn't operation room, even can be done at the patient's bedside. Its merits the included point wound without craniotomy, low medical cost and satisfactory result. We treat 112 patients with hypertensive intracranial hematomas, 25 patients with acute epidural hamatoma and 17 patients with hematoma due to other causes. In the total of 154 patients, 20 had brain herniations and 104 coma. The mortality was very low (8.44%). 94 patients (91.34%) woke up in 1 to 2 weeks.

Cerebral Hemorrhage↗

[Cholesterol granulomatous tympano-mastoiditis].

In order to investigate the early diagnosis and proper management of the cholesterol granulomatous tympanomastoiditis, 6 cases verified by pathology and surgery were reviewed. All of these cases had a longterm or a historical otitis media. Among them, different clinical features were presented, such as chronic serous otitis media, idiopathic blue eardrum, or as a primary occupying lesion of the middle ear. Depend on the extension of the disease, surgical procedure varied in the 6 cases, including exploratory tympanotomy, ventilation tube insertion, antroatticotomy, simple mastoidectomy, and radical mastoidectomy. Postoperative follow up for at least one--7 year showed no recurrence, and hearing improvement in 5 cases. The clinical basis of the diagnosis and management of this disease were also discussed.

Adolescent↗

[Cloning and identification of recombinant cDNA to a rabbit oviductin "DPF-1"].

A recombinant cDNA library to polyA + RNA isolated from rabbit oviduct epithelial cells was constructed, and screened with a polyclonal antibody against DPF-1 (64 kDa). 4 immunopositive plaques (DPF-1.1, DPF-1.2, DPF-1.3 and DPF-1.4) were purified. The polyclonal antibodies were epitope-selected respectively against the fused proteins produced by these positive recombinant plaques. Identification of recombinant clones by epitope selection revealed that the epitope-selected antibodies from DPF-1.1, DPF-1.2 and DPF-1.3 could recognise not only DPF-1, but 44 kDa protein also (Fig. 2). By using EcoRI-Not1 digestion method, the insert cDNA fragment size of these three recombinants was revealed to be 0.8 kb, 1.2 kb and 1.2 kb respectively (Fig. 3). These cDNA fragments were then isolated and subcloned into pBluescriptKS, and recombinant plasmids (pDPF-1.1, pDPF-1.2 and pDPF-1.3) were constructed (Fig. 4). Dot blot hybridization with a 32p-labeled 1.2 Kb-insert of cDNA from pDPF-1.3 indicated that these recombinant plasmids could cross-hybridized (Fig. 5), further indicating that they all possessed a common nucleic acid sequence. Dot and Northern blotting analysis of total RNA prepared from eight different tissues (skeleton muscle, heart, kidney, oviduct, liver, spleen, lung and small intestine) showed that the gene encoding DPF-1 was expressed specifically in the oviduct tissue (Fig. 6, Fig. 7).

Animals↗

[Preliminary studies on the rabbit oviductin "DPF-1"].

Anti-rabbit 64 kDa oviductin (named Development Promoting Factor-1, DPF-1) antibody could inhibit totally the early development of mouse fertilised eggs cultured in the conditioned medium derived from the rabbit oviduct mucosa epithelial cells, revealed that DPF-1 synthesized and secreted from rabbit oviduct mucosa has a function to overcome the developmental block of early mouse embryos. It seems that DPF-1 consists of a group of polypeptide isoforms, since its isoelectric points are ranging from 7.2 to 8.1 (Fig. 3). The synthesis and secretion of DPF-1 was not dependent on either 17 beta-estradiol or progesterone (Fig. 7), it can pass through zona pellucida easily and associate tightly with the early embryonic cell membrane (Fig. 6). By using Western blotting method, we found that DPF-1 was not appeared in the tissues of liver, heart, lung, spleen, uterus, ovary, small intestine, skeleton muscle and brain, but in that of oviduct (Fig. 4): some DPF-1 homologous molecules were also revealed in the oviduct tissues of mouse and golden hamster, their apparent molecular weights were 32 kDa, 72 kDa in mouse, and 49 kDa, 68 kDa in golden hamster (Fig. 5). Results obtained from the in vivo anti-fertility experiment, namely to analyse the anti-fertility effect in adult female mice after active immunization with DPF-1, showed that the fertility decreased significantly as compared to those of controls (p < 0.01) (Table 1). DPF-1 and its in vivo "loss of function" evidence we obtained will encourage us to study the mechanism of DPF-1 in overcoming the developmental block of early embryos, and its role in transition from maternal to embryonic control of early development.

Animals↗

Anti-lipid peroxidation of gomisin J on liver mitochondria and cultured myocardial cells.

AIM: To study the influences of gomisin J on lipid peroxidation and calcium paradox. METHODS: Using two in vitro models of rat liver mitochondria membrane lipid peroxidation (LPO) and cultured myocardial cells. RESULTS: Gomisin J inhibited Fe2+/ascorbic acid and ADP/NADPH-induced LPO with IC50 (95% confidence limits) 5.5 (4.5-6.7) and 4.7 (2.8-7.8) mumol.L-1, respectively, when cultured myocardial cells preincubated with Ca(2+)-free medium for 2 min were incubated with normal medium containing Ca2+, a marked increase of malondialdehyde (MDA) formation occurred and gomisin J 10 mumol.L-1 protected myocardial cells through decreasing MDA formation. CONCLUSION: Gomisin J inhibits LPO in rat liver mitochondria and protects cultured myocardial cells from being injured by calcium paradox.

Animals↗

Effects of non-nucleoside inhibitors of human immunodeficiency virus type 1 in cell-free recombinant reverse transcriptase assays.

We have employed a cell-free human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) assay to study the effects of non-nucleoside inhibitors of RT (NNRTI) by directly monitoring specific HIV DNA products using a HIV-1 genome-derived template and an oligodeoxynucleotide primer. As previously shown by ourselves and others, nucleoside analog triphosphates, e.g. 3'-azido-3'-deoxythymidine triphosphate and 2',3'-dideoxyadenosine triphosphate, could directly inhibit HIV RT RNA-dependent DNA polymerase activity by causing chain termination, as visualized in a RT reaction that yields specific DNA products. In contrast, each of two NNRTIs, nevirapine and delavirdine, directly inhibited RT activity without causing chain termination effects. We also analyzed interactions between nucleoside analogs and NNRTIs or among NNRTIs by chain elongation/dNTP incorporation and/or steady-state kinetic assays. Combinations of nevirapine with the triphosphates of either the (-)-strand of 2',3'-dideoxy-3'-thiacytidine or 2',3'-dideoxyadenosine yielded additive/synergistic effects on RT activity. However, only an additive effect was observed when combinations of nevirapine and 3'-azido-3'-deoxythymidine triphosphate were employed. Combinations of nevirapine and delavirdine had an antagonistic effect on the inhibition of HIV-1 RT activity.

Cell-Free System↗

Envelope V3 region sequences of Cuban HIV-1 isolates.

The origin of HIV-1 species, responsible for the AIDS epidemic in Cuba, is a subject that has been intensely debated. This study represents an initial attempt to shed light on this issue, through sequence analysis of the V3 regions of viruses isolated from 15 Cuban subjects. We now report that these viruses fall within three distinct, well-recognized groupings. These findings suggest that viruses of different sources are responsible for the HIV/AIDS epidemic in Cuba.

Acquired Immunodeficiency Syndrome↗

Mutated K65R recombinant reverse transcriptase of human immunodeficiency virus type 1 shows diminished chain termination in the presence of 2',3'-dideoxycytidine 5'-triphosphate and other drugs.

A lysine-to-arginine substitution at amino acid 65 (K65R) in human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) is associated with resistance to 2',3'-dideoxycytidine (ddC), 2',3'-dideoxyinosine (ddI), and the (-) enantiomer of 2',3'-dideoxy-3'-thiacytidine (3TC). To further characterize the molecular basis of such resistance, we expressed the pp6/p51 heterodimer of wild-type RT, K65R mutated RT, and a doubly mutated (K65R/M184V) RT in Escherichia coli and assessed the characteristics of nucleotide incorporation and chain termination in cell-free reverse transcription reactions in the presence and absence of various nucleoside triphosphate analogs. These reactions employed a HIV RNA template (HIV-PBS) that contained the primer binding sequence (PBS) and the U5 and R regions of HIV-1 genomic RNA and an oligodeoxynucleotide (dPR) complementary to the HIV-1 PBS as primer. The K65R and K65R/M184V RTs showed significantly decreased chain-termination effects during polymerization with the 5'-triphosphates of ddC, 3TC, 2',3'-dideoxyadenosine, and AZT (3'-azido-3'-deoxythymidine) in comparison with wild-type RT. Detailed analysis with ddCTP and wild-type RT revealed that chain termination occurred at all guanines in the RNA template. However, the frequency of dideoxynucleoside triphosphate (ddNTP)-induced chain termination was decreased at certain guanines but not others in reactions catalyzed by K65R RT. Both the K65R mutant RT and wild-type RT had similar processive activity. These results indicate that decreased chain termination of K65R RT in the presence of ddNTPs is consistent with data obtained in viral replication assays.

Arginine↗

Social aspects of malaria in Heping, Hainan.

This paper presents findings from a study conducted in Heping Town, Qiongzhong County, Hainan Province, China. The study, conducted in 1992, used qualitative as well as quantitative methods to gather social, cultural and behavioural data associated with the acquisition, transmission and prevention of malaria, and the diagnosis and treatment of disease. These methods included focus groups, key informant and other in-depth interviews, and observations, a household survey and tests of school children of knowledge of malaria. The study is among the first to our knowledge that has utilized this broad mix of methods for tropical disease research in China.

Adolescent↗

A morphometric study on the endometrial activity of women before and after one year with LNG-IUD in situ.

The endometrium was studied by morphometry in 34 healthy women before and after one year's use of an IUD releasing levonorgestrel at a rate 20 micrograms/24 hr (LNG-IUD-20). The effect was compared with that of an IUD releasing 2 micrograms levonorgestrel/24 hr (LNG-IUD-2). The appearance of suppressed endometrial proliferative activity and increased inflammatory reaction was similar in the two experimental groups, suggesting that the morphological alterations were independent of the LNG dosage. The result of this study, combined with clinical data, suggests that LNG-IUD-20 could replace LNG-IUD-2 without any additional side effects. The efficacy of LNG-IUD-20 is also likely to last for a longer period than the LNG-IUD-2.

Adult↗

The effect of levonorgestrel-releasing intrauterine device (20 micrograms/day) (LNG-IUD-20) on the morphological structure of human endometrium: a study of the endometrial factor VIII activity in the women before and after insertion of LNG-IUD-20 by the digital image analysis.

The specimens of endometria were obtained from 18 women using an intrauterine device releasing levonorgestrel at 20 micrograms/day (LNG-IUD-20). An immunoperoxidase reaction, PAP method, with the antiserum of Factor VIII as the primary antibody, was carried out in the endometrial biopsies to detect the Factor VIII activity in the endometrial endothelium before and after insertion of LNG-IUD-20. The immunoperoxidase activity was quantitatively assessed by a computer digital image analyser. The results revealed that there were a lower Factor VIII activity in the endometrial endothelial cells after insertion of LNG-IUD-20 (p < 0.001) when compared with the control. From the results of the present study, it is suggested that the synthesis and release of endometrial endothelial Factor VIII might be inhibited by the insertion of LNG-IUD20.

Adult↗